This invention relates to aromatic thermoplastic materials, particularly thermoplastic materials having enyne moieties in the polymer backbone.
Fiber-reinforced composites are widely used in a great variety of applications. Generally such composites have heretofore employed thermosetting resins. In recent years there has been increased interest in utilizing thermoplastic materials in place of the thermosetting materials, in order to reduce the processing cost of such fiber-reinforced composites. In order to replace thermosetting materials with thermoplastic materials, the latter must exhibit enough of the desirable physical and chemical properties of the former to make the exchange worthwhile. For certain applications, the polymeric material must be resistant to attack by solvents, such as paint strippers and brake and hydraulic fluids. It is also desirable that the polymeric material be suitable for use in a high temperature environment, i.e., at a temperature of about 200.degree. C. and above. Known thermoplastic polymers having the desired high temperature property also have high glass transition temperatures, thus require high fabrication temperatures. What is desired is a thermoplastic polymer having a relatively low glass transition temperature, which can be employed in high temperature environments and which has low solvent susceptibility.
It is therefore an object of the present invention to provide a novel thermoplastic polymeric material.
It is another object of this invention to provide a process for producing a novel thermoplastic polymeric material.
It is yet another object of this invention to provide a new composition of matter.
Other objects and advantages of the present invention will be apparent to those skilled in the art from a consideration of the following disclosure.
In accordance with the present invention there is provided a thermoplastic polymer having the following general formula: ##STR1##
In a presently preferred embodiment the polymer I has the cis-enyne configuration, as illustrated, for example, by the following formula: ##STR2##
The polymer I is made by reacting a di-.beta.-bromovinyl benzene and a diacetylenic compound in the presence of a suitable catalyst in a suitable reaction medium, as illustrated by the following reaction: ##STR3##
The di-.beta.-bromovinyl benzene reactants which may be employed in this invention include cis- and trans-1,2-di-.beta.-bromovinyl benzene, -1,3-di-.beta.-bromovinyl benzene, and -1,4-di-.beta.-bromovinyl benzene, and cis- and trans-1,2-bis(2-bromo-2-phenylvinyl)benzene, -1,3-bis(2-bromo-2-phenylvinyl)benzene, and -1,4-bis(2-bromo-2-phenylvinyl)benzene.
The di-.beta.-bromovinyl benzenes may be prepared by reacting a phenylenediacrylic acid with bromine and thereafter treating the intermediate product with a suitable base, such as sodium bicarbonate, as illustrated by the following reaction ##STR4##
The diacetylenic compounds which may be employed in this invention include diethynyl benzene, di-p-ethynylphenyl ether, 1,3-bis(3-ethynylphenoxy)benzene, 4,4'-bis(3-ethynylphenoxy)diphenylsulfone, 4,4'-bis(4-ethynylphenoxy)diphenylsulfone, di-p-ethynylphenylthioether, 1,3-bis(3-ethynylthiophenoxy)benzene, 4,4'-bis(3-ethynylphenoxy)benzophenone, 2-(4-ethynylphenyl)-5-ethynylbenzothiazole, 2-(3-ethynylphenyl)-5-ethynylbenzothiazole, 2-(4-ethynylphenyl)-6-ethynylbenzothiazole, 2-(3-ethynylphenyl)-6-ethynylbenzothiazole, N-(3-ethynylphenyl)-4-(3-ethynylphenoxy)naphthalimide, N-(4-ethynylphenyl)-4-(3-ethynylphenoxy)naphthalimide, N-(3-ethynylphenyl)-4-(4-ethynylphenoxy)naphthalimide, N-(4-ethynylphenyl)-4-(4-ethynylphenoxy)naphthalimide, N-(3-ethynylphenyl)-3-(3-ethynylphenoxy)phthalimide, N-(3-ethynylphenyl)-3-(4-ethynylphenoxy)phthalimide, N-(4-ethynylphenyl)-3-(3-ethynylphenoxy)phthalimide, N-(4-ethynylphenyl)-3-(4-ethynyl-phenoxy)phthalimide, 2,2-bis[N-(3-ethynylphenyl)-4-phthalimido]hexafluoropropane, 2,2-bis[N-(4-ethynylphenyl)-4-phthalimido]hexafluoropropane, and the like.
The reaction is carried out under an inert atmosphere in a liquid reaction medium consisting essentially of an aprotic solvent, such as N,N-dimethylacetamide, and from about 10 to 50 percent (v/v) of an HBr acceptor, such as triethylamine. Suitable inert atmospheres include dry nitrogen, argon, helium, Xenon and the like.
The catalyst system consists essentially of cuprous iodide and bis-triphenylphosphine palladium II dichloride. These ingredients are employed in a weight ratio of about 1:2 (cuprous iodide:Pd II complex), and the amount of this catalyst mixture can range from about 2 to about 10 percent by weight of the weight of the reactants.
The reaction may be carried out at a temperature in the approximate range of 5.degree. to 40.degree. C., preferably about 20.degree. to 25.degree. C. The reactants are dissolved in the liquid reaction medium described above and the resulting mixture is stirred for about 24 to 100 hours. The polymer I may be separated from the reaction mixture by pouring the mixture into a suitable liquid which is a non-solvent for the polymer, such as, for example, methanol. The polymer I is then recovered in conventional fashion.